ANSICHTSKARTE Krauseneck, Gustav Adolf Author: Krauseneck, Gustav Adolf Recipient: Haeckel, Ernst Dating: 30.12.1913
ANSICHTSKARTE Haeckel, Walther Author: Haeckel, Walther Recipient: Haeckel, Ernst; Haeckel, Agnes [Eltern] Dating: 16.10.1913
ANSICHTSKARTE Haeckel, Walther Author: Haeckel, Walther Recipient: Haeckel, Ernst; Haeckel, Agnes [Eltern] Dating: 14.11.1913